In recent years, an optical disc player device has become widespread in household-use for an optical disc that has an advanced interactive function with high-definition images and high quality sounds and has a large amount of information recorded thereon.
A typical high capacity optical disc is a Blu-ray Disc (hereinafter referred to as “BD”). A BD is provided with a huge data capacity: 25 gigabytes (GB) in a single layer and 50 GB in a dual layer, and can store high definition movie content. Commercially available or rental-use packaged software using the BD is supplied as a BD-ROM that is a read-only media in which data is written in the course of manufacture and which is not recordable and not rewritable.
For the BD-ROM, two modes of specifications have been developed: High Definition Movie (HDMV) mode and Blu-Ray Disc Java (BD-J) mode. In the HDMV mode, codec specification for video and sound is extended from a conventional Digital Versatile Disc Read Only Memory (DVD-ROM), and high definition video and high quality audio are available. It is noted that content specification of a BD-ROM is similar to that of a DVD-ROM. In the BD-J mode, in addition to the HDMV mode, visual representation such as a superimposed video can be added by a Java® application.
An operation in which a disc player device plays a BD-ROM will now be described.
A BD-ROM such as packaged software is managed on a basis of a plurality of reproducible titles. Some titles are played before playing of a main part or display of a menu (hereinafter, the title is referred to as a “first play”) among the plurality of titles when the power is turned on. A first play is an introduction of other packaged software, a movie preview, demonstration content for sound field playing technology, or the like. Some packaged software takes as long as five minutes in a first play when the first play is played at a normal speed.
In addition, in each title including a first play, a user operation can be restricted by a user operation mask (hereinafter referred to as “UO mask”). UO mask refers to a restriction on user operations such as a button operation of a menu screen, menu shift, title skip, stop playing, chapter selection, fast forward, and reverse play that are used when a user watches and listens to packaged software.
When UO mask is set, any user operation is restricted by a software module that serves to accept a user operation. With the function, an operation intended by a content provider can be realized.
Accordingly, in a household-use BD player device, when it is desired that video of a main part are played as soon as possible after a disc is inserted, a user operation such as menu shift, title skip, and fast forward can be performed by operating a remote control and a time of a first play can be reduced if UO mask is not set to the first play.
In addition, it has been proposed to play a digital stream recorded in a recording medium such as an optical disc by an operation without a Graphical User Interface (GUI) similar to an operation of a Compact Disc (CD) player device when a BD-ROM player device is used in a car (for example, see Patent Literature 1).
However, in many cases where a disc player device is used in a car, a driver is barred from operating the disc player device during the movement of the vehicle, and a playing time of a first play cannot be reduced by operating a remote control.
Especially, in a BD-J title, continued playing (resume playing) is not practical when the playing is resumed after the car engine is turned off or an instantaneous power interruption occurs because a lot of memory is needed. Therefore, generally, when these events occur, the playing is started again from a first play. For example, when the car engine is turned off to take a rest during car travel and the power is turned on again after taking the rest, a first play of the same content is played for a few minutes every time and then video of a main part is played.